NOTE: As their name suggests hints are not exactly Resident Evil 6 cheats, and are usually just simple (but very useful) tips on how you can unlock secret level, features, find hidden areas and such. Hopefully these will make playing Resident Evil 6 even more entertaining.

Steam Achievements
A Revolting Development: Complete Chapter 2 in Jake's campaign.
Ada's Demise: Complete Chapter 4 in Ada's campaign.
After Her!: Complete Chapter 3 in Chris' campaign.
B.O.W.s Are Ugly: Defeat 100 enemies that have come out of a chrysalid.
Back in My Day: Complete the entire game on Veteran.
Big Trouble in China: Complete Chapter 4 in Leon's campaign.
Bob and Weave: Counter an enemy's attack three times in row.
Bring the Heat: Take down an enemy from 50 meters away with a headshot using the thermal scope.
Buried Secrets: Complete Chapter 2 in Leon's campaign.
Check Out My Dogs: Customize your dog tags.
Civilian Casualties: Defeat the BSAA 100 times.
Counterintelligence: Complete Chapter 2 in Ada's campaign.
Covered in Brass: Earn 150 different medals.
Down, Not Out: Defeat an enemy while dying, then recover without any help.
Duty Calls: Complete Chapter 5 in Chris' campaign.
Easy Pickings: Eliminate all players as Ustanak in less than a minute.
Everybody Dies: Defeat 100 player-controlled agents and 100 player-controlled creatures.
Finish What You Start: Perform a coup de grâce on ten enemies.
Flying Ace: Pilot the VTOL without getting a scratch on it.
Get on the Plane: Complete Chapter 3 in Leon's campaign.Give a Little Push: Knock ten enemies off a high place.
Gone to Hell: Complete Chapter 1 in Leon's campaign.
Green around the Ears: Complete the entire game on Amateur.
Hard Choice: Shoot the helicopter pilot with a Magnum at point-blank range.
Heirlooms: Collect all the serpent emblems.
Held Captive: Defeat Ustanak with only one Agent remaining.
High Voltage: Defeat ten enemies with a stun rod charge attack.
I Prefer Them Alive: Rescue two female survivors at the cathedral.
I Spy: Complete Chapter 1 in Ada's campaign.
Invincible: Defeat Ustanak without anyone on your team being captured.
J'avo Genocide: Defeat 500 J'avo.
Kill or Be Killed: Win while in the dying state.
Killer Combo: Achieve a 30-combo chain.
Kung Fu Fighting: Survive to the end only using physical attacks.
Last Man Standing--Again: Win five times in a row.
Leave It to the Pro: Complete the entire game on Professional.
Let's Blow This Joint: Complete Chapter 3 in Jake's campaign.
Lifesaver: Help or rescue your partner ten times.
Mad Skillz: Max out all the skills that allow you to level up.
Money Talks: Complete Chapter 1 in Jake's campaign.
Murder Spree: Defeat the BSAA as a creature without dying once.
Normal Is Good: Complete the entire game on Normal.
Not without a Fight: Defeat Ustanak 20 times.
One Is Better Than None: Purchase one skill.
One Is Never Enough: As Ustanak, capture a total of 50 humans.
Protect and Serve: Protect the BSAA without any of them getting hurt.
Rescue the Hostages: Complete Chapter 1 in Chris' campaign.
Rising Up: Earn a level-four title.
See You Around: Complete Chapter 5 in Jake's campaign.
Silent Killer: Use a stealth attack to take down five enemies.
Sneaking Around: Get through the aircraft carrier's bridge area without being noticed.
Staying Alive: Return to the game as a human character.
Still on the Run: Complete Chapter 4 in Jake's campaign.
Stuntman: Defeat 20 enemies with the Hydra using a quick shot.
Surrounded on All Sides: Send 2,000 enemies to your opponent's map.
Take 'Em All Down: Defeat 100 agents.
Take the Stage: Defeat your opponent and achieve victory in 3 stages.
Team Effort: Win without any members of your team being killed.
The Longest Night: Complete the tutorial.
The Trouble with Women: Complete Chapter 5 in Leon's campaign.
There's Always Hope: Complete Chapter 4 in Chris' campaign.
They're ACTION Figures!: Collect 3 figures.
This Takes Me Back: Complete Chapter 3 in Ada's campaign.
Titular Achievement: Earn 10 different titles.
Tragedy in Europe: Complete Chapter 2 in Chris' campaign.
Two Sides of the Same Coin: Win 10 times.
Weapons Master: Use all the weapons in the game and kill ten enemies with each of them.
What's Next?: Complete Chapter 5 in Ada's campaign.
You Are S.O.L.: Defeat your opponent 10 times with enemies you sent.
Zombie Massacre: Defeat 500 zombies.

Extra Content (Characters/Costumes)
Costumes and characters, once unlocked, can be used in all Extra Content modes. Carla, Agent, and the Left 4 Dead 2 characters do not have alternate costumes. In solo mode, A rank is awarded for 100,000 points, B rank for 80,000 points. In duo mode, A rank is awarded for 180,000 points, B rank for 120,000 points.